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Fixational Eye Movements in the Earliest Stage of Metazoan Evolution
All known photoreceptor cells adapt to constant light stimuli, fading the retinal image when exposed to an immobile visual scene. Counter strategies are therefore necessary to prevent blindness, and in mammals this is accomplished by fixational eye movements. Cubomedusae occupy a key position for un...
Autores principales: | , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Public Library of Science
2013
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3679052/ https://www.ncbi.nlm.nih.gov/pubmed/23776673 http://dx.doi.org/10.1371/journal.pone.0066442 |
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author | Bielecki, Jan Høeg, Jens T. Garm, Anders |
author_facet | Bielecki, Jan Høeg, Jens T. Garm, Anders |
author_sort | Bielecki, Jan |
collection | PubMed |
description | All known photoreceptor cells adapt to constant light stimuli, fading the retinal image when exposed to an immobile visual scene. Counter strategies are therefore necessary to prevent blindness, and in mammals this is accomplished by fixational eye movements. Cubomedusae occupy a key position for understanding the evolution of complex visual systems and their eyes are assumedly subject to the same adaptive problems as the vertebrate eye, but lack motor control of their visual system. The morphology of the visual system of cubomedusae ensures a constant orientation of the eyes and a clear division of the visual field, but thereby also a constant retinal image when exposed to stationary visual scenes. Here we show that bell contractions used for swimming in the medusae refresh the retinal image in the upper lens eye of Tripedalia cystophora. This strongly suggests that strategies comparable to fixational eye movements have evolved at the earliest metazoan stage to compensate for the intrinsic property of the photoreceptors. Since the timing and amplitude of the rhopalial movements concur with the spatial and temporal resolution of the eye it circumvents the need for post processing in the central nervous system to remove image blur. |
format | Online Article Text |
id | pubmed-3679052 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2013 |
publisher | Public Library of Science |
record_format | MEDLINE/PubMed |
spelling | pubmed-36790522013-06-17 Fixational Eye Movements in the Earliest Stage of Metazoan Evolution Bielecki, Jan Høeg, Jens T. Garm, Anders PLoS One Research Article All known photoreceptor cells adapt to constant light stimuli, fading the retinal image when exposed to an immobile visual scene. Counter strategies are therefore necessary to prevent blindness, and in mammals this is accomplished by fixational eye movements. Cubomedusae occupy a key position for understanding the evolution of complex visual systems and their eyes are assumedly subject to the same adaptive problems as the vertebrate eye, but lack motor control of their visual system. The morphology of the visual system of cubomedusae ensures a constant orientation of the eyes and a clear division of the visual field, but thereby also a constant retinal image when exposed to stationary visual scenes. Here we show that bell contractions used for swimming in the medusae refresh the retinal image in the upper lens eye of Tripedalia cystophora. This strongly suggests that strategies comparable to fixational eye movements have evolved at the earliest metazoan stage to compensate for the intrinsic property of the photoreceptors. Since the timing and amplitude of the rhopalial movements concur with the spatial and temporal resolution of the eye it circumvents the need for post processing in the central nervous system to remove image blur. Public Library of Science 2013-06-11 /pmc/articles/PMC3679052/ /pubmed/23776673 http://dx.doi.org/10.1371/journal.pone.0066442 Text en © 2013 Bielecki et al http://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are properly credited. |
spellingShingle | Research Article Bielecki, Jan Høeg, Jens T. Garm, Anders Fixational Eye Movements in the Earliest Stage of Metazoan Evolution |
title | Fixational Eye Movements in the Earliest Stage of Metazoan Evolution |
title_full | Fixational Eye Movements in the Earliest Stage of Metazoan Evolution |
title_fullStr | Fixational Eye Movements in the Earliest Stage of Metazoan Evolution |
title_full_unstemmed | Fixational Eye Movements in the Earliest Stage of Metazoan Evolution |
title_short | Fixational Eye Movements in the Earliest Stage of Metazoan Evolution |
title_sort | fixational eye movements in the earliest stage of metazoan evolution |
topic | Research Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3679052/ https://www.ncbi.nlm.nih.gov/pubmed/23776673 http://dx.doi.org/10.1371/journal.pone.0066442 |
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